U.S. patent number 3,676,538 [Application Number 05/008,494] was granted by the patent office on 1972-07-11 for method for soap bars having marble-like decoration.
This patent grant is currently assigned to Purex Corporation, Ltd.. Invention is credited to Charles B. Patterson.
United States Patent |
3,676,538 |
Patterson |
July 11, 1972 |
**Please see images for:
( Certificate of Correction ) ** |
METHOD FOR SOAP BARS HAVING MARBLE-LIKE DECORATION
Abstract
Method of producing marble-like appearance in a soap bar in
which a saponaceous dye solution having color contrast with the
soap of the bar is injected through a screw end opening in a
plodder screw and is distributed through a soap mass being extruded
in a manner producing contrasting color streaks therethrough
subdued at their boundaries for indistinct mergence with the
extruded mass.
Inventors: |
Patterson; Charles B.
(Lakewood, CA) |
Assignee: |
Purex Corporation, Ltd.
(Lakewood, CA)
|
Family
ID: |
21731918 |
Appl.
No.: |
05/008,494 |
Filed: |
February 4, 1970 |
Current U.S.
Class: |
264/75; 510/440;
264/211; 425/131.1; 510/146; 264/171.1; 159/DIG.14; 264/245 |
Current CPC
Class: |
B29C
48/175 (20190201); C11D 13/08 (20130101); C11D
13/18 (20130101); Y10S 159/14 (20130101); B29C
48/06 (20190201) |
Current International
Class: |
B29C
47/04 (20060101); C11D 13/00 (20060101); C11D
13/18 (20060101); C11D 13/08 (20060101); B29f
003/12 (); B32b 031/30 (); C11d 013/18 () |
Field of
Search: |
;264/75,73,245,211,349,173,176,171 ;18/8 ;252/134,109,371,367,370
;159/DIG.14 ;25/8 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: White; Robert F.
Assistant Examiner: Thurlow; Jeffery R.
Claims
I claim:
1. In the operation of a soap plodder in which a mass of formable
soap is advanced by a rotating screw under compression through a
tubular barrel, an apertured pressure plate beyond the screw end,
and a convergent outlet; the method of producing bar soap having
marble-like appearance that includes injecting from the pressure
plate end of the screw through a screw end opening offset from the
screw axis a colorant fluid having color contrast with the soap
mass and in relatively small proportion, and extruding the
resulting mixture through apertures so arranged in the pressure
plate as to distribute and maintain the colorant fluid unevenly
within the soap mass to produce in and through the soap
convergingly discharged from the plodder color streaks subdued at
their boundaries for indistinct mergence with the extruded
mass.
2. Method according to claim 1 including injecting a saponaceous
colorant solution into the soap mass as said colorant fluid.
3. Method according to claim 1 including displacing colorant fluid
from its injection locus as a coherent stream in the soap mass
moving between said injection opening and said pressure plate.
4. Method according to claim 1 including also arranging the
pressure plate apertures in a manner to preferentially distribute
colorant fluid therethrough.
5. Method according to claim 1 including also rotating said feed
inlet with the screw in a locus less than 0.75 inch from said
pressure plate.
6. Method according to claim 1 including also two sets of different
diameter apertures in the pressure plate and passing successive
portions said soap mass with dye solution therein alternately
through apertures of one or another of said sets.
7. Method according to claim 1 including adding colorant fluid to
the soap mass in an amount equal to between 0.1 and 10 percent of
the soap mass weight.
8. Method according to claim 2 including also dissolving from 2 to
25 percent by weight of soap in said colorant solution prior to
injecting the solution into said soap mass.
9. Method according to claim 1 in which said colorant fluid is
introduced into the soap mass from said opening along a circular
locus uniformly spaced from said pressure plate.
10. Method according to claim 9 including also injecting a
saponaceous dye solution containing from 2 to 25 percent by weight
of soap into said soap mass in an amount equal to between 0.1 and
10 percent of the weight of the soap mass.
11. Method according to claim 1 including also longitudinally
distributing said colorant fluid through the soap mass downstream
of said pressure plate generally parallel to the axis of said
convergent outlet by the convergent movement of the soap mass
containing said fluid passing through said outlet.
12. Method according to claim 1 including maintaining a series of
apertures downstream from the locus of colorant fluid injection
into the soap mass.
13. Method according to claim 1 in which said inlet introduces said
saponaceous dye solution into the soap mass along a circular locus
concentric with the screw axis and having a radius equal to between
35 and 65 percent of the screw radius.
14. Method according to claim 1 in which said saponaceous dye
solution is introduced intermittently into the soap mass from said
inlet.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
Decoration of bar soap has generally been limited to overall
coloring and surface ornamentation with stampings. Use of
contrasting color decoration in a single soap bar, particularily
such decoration having a marble-like appearance, has been long
sought, but not obtained in a commercially acceptable soap bar. The
reason appears to be either the difficulty of duplicating the
random yet regular pattern characteristic of marble and
particularly at more than surface portions of the bar, or the
deterioration of bar properties coincident with the introduction of
foreign material into the bar. Such deterioration is manifested by
cracking of the bar, in production or prematurely in use.
2. Prior Art
As indicated, attempts have been made in the past to obtain
marbleized and/or multicolored patterns of decoration in soap bars.
These efforts have included elaborate dies which coextrude
differently colored soap materials in predetermined patterns and
complicated apparatus for introducing preformed colored bodies into
a soap mass to be partially mixed therewith. In such methods the
interface of colored and background soap is likely to be too sharp
for a marble-like appearance and because the interface is a
distinct boundary, cracking of the bar therealong is a likely
occurrence. Such cracking is detrimental to building consumer
acceptance of a marbleized soap bar.
SUMMARY OF THE INVENTION
Accordingly, it is a major objective of the present invention to
provide method for the production of soap bars having a marble-like
appearance in which true marbleizing is realized and without the
hitherto concomitant complexities in apparatus, formulation or
extrusion.
The invention may be considered to have reference to the operation
of a soap plodder or other final soap forming device in which a
mass of formable soap is advanced by a rotating screw under
compression through a tubular barrel, a apertured pressure plate
beyond the screw end, and a convergent outlet. In accordance with
the invention, a method is provided for producing bar soap having a
marble-like appearance that includes injecting from the pressure
plate end of the screw through an opening offset from the screw
axis a colorant fluid having color contrast with the soap mass and
in relatively small proportion, and extruding the resulting mixture
through apertures so arranged in the pressure plate as to
distribute and maintain the colorant fluid unevenly within the soap
mass to produce in and through the soap convergingly discharged
from the plodder color streaks subdued at their boundaries for
indistinct mergence with the extruded mass. Particular features of
the method include: injecting a saponaceous solution of colorant
e.g. a dye solution containing 2 to 25 percent by weight soap into
the extruded soap mass in an amount equal to between 0.1 to 10
percent of the soap mass weight; displacing the colorant fluid from
its injection locus as a coherent stream in the soap mass moving
between the injection opening and the pressure plate apertures;
arranging the pressure plate apertures in a manner to
preferentially distribute colorant fluid through the pressure plate
apertures; introducing the colorant fluid into the soap mass from
the opening along a circular locus uniformly spaced from the
pressure plate; maintaining a series of apertures downstream from
the locus of colorant fluid injection in the soap mass; injecting
the colorant fluid uniformly or intermittently; and longitudinally
distributing the colorant fluid through the soap mass downstream of
the pressure plate generally parallel to the axis of the convergent
outlet by the convergent movement of the soap mass containing the
colorant fluid passing through the outlet.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a marble-like appearing soap bar
according to the invention;
FIG. 2 is a partly schematic view of a final soap plodder and
colorant fluid feed system therefor, the plodder being shown in
section;
FIG. 3 is a horizontal section of the plodder taken on line 3--3 in
FIG. 2 and greatly enlarged;
FIG. 4 is an end elevation view of the plodder screw and barrel,
taken along line 4--4 in FIG. 3 and showing the plodder pressure
plate apertures in phantom outline;
FIG. 5 is an elevation view of the plodder and pressure plate taken
along line 5--5 in FIG. 3; and
FIG. 6 is a view like FIG. 5 showing an alternate aperture
arrangement in a pressure plate.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The term "colorant fluid" herein refers to a fluent or fluid
material, solid or liquid having color contrast with a soap mass
into which it is injected. The colorant fluid is preferably liquid
and saponaceous solution e.g. of a dye or pigment but may also be a
suspension or emulsion of pigment or dye in water, alcohol,
glycerine or other liquid compatible with the soap mass, or be a
fluent, powdered pigment or dye.
The typical final product obtainable with the present method is
shown in FIG. 1. Soap bar 1 has marbled top, side and end surfaces
2 marbled with contrasting three-dimensional streaks 3 and the
marbling effect continues throughout the bar, so that upon wearing
through use, the marble pattern continues with subtle variation in
geometry and nearly imperceptible nuance of color change at
different levels of the bar as the veins of coloration are
gradually progressively exposed. While the term "marble-like" in
appearance best describes the decorative effect seen in soap bar 1,
words may be used to convey the aesthetic impression. Thus, a
marble-like appearance is one in which numerous, discrete
contrasting color streaks or striations each with variations in
width and depth along their length appear in approximately parallel
array. The appearance is distinguished from mere striping in the
irregularity of the striation contour and particularly by the
manner in which the color streaks are subdued at their boundries
for indistinct mergence with the extruded mass.
The base material or "soap mass" for the soap bar 1 may be made
generally as for a milled soap. That is it may consist mainly of
the sodium salts of the fatty acids of a mixture of 18 percent
coconut oil and 82 percent tallow, rancidity preventing agents in
minor proportions, 1.0 percent perfume, 0.6 percent titanium
dioxide whitening agent, and approximately 13 percent moisture.
This formulation is prepared by methods for making milled soap that
are well known in the soap industry. These methods typically
include boiling the mixture of fats with caustic soda to obtain
"kettle" soap, mixing in rancidity preventing agents, drying to
obtain white soap chips having approximately 13 percent moisture
content, admixing 1.0 percent perfume and 0.6 percent titanium
dioxide with the chips, kneading and working by milling and
extruding first through a preliminary plodder to obtain
spaghetti-like noodles and then through a final plodder to obtain a
solid, rod-like extrusion termed a "plodder strip," which is
self-supporting but moldable. This plodder strip is cut into
appropriate length sections and molded into the final bar shap in
suitable dies. The above-stated formulation and preparation apply
to particular techniques actually employed in the development of
the soap bar depicted at 1 in the drawing, and is intended to be
illustrative of milled soap manufacture and suggestive of other
suitable means of accomplishing the same result. Otherwise formed
moldable soap masses may also be marbleized according to the
invention with whatever adjustment of colorant fluid viscosity,
composition and the like may be appropriate.
The present method will be described with respect to an
illustrative embodiment as commencing with the introduction of the
spaghetti-like noodles of milled soap from the milling and
preliminary plodding operations into hopper 4 of final plodder 5.
The screw 6 is mounted for axial rotation within the barrel 7 of
the plodder 5 and carries the soap mixture forward (left to right)
through the plodder barrel ultimately for discharge through the
compression cone 8 fixed in the end 9 of the barrel 7 by means not
shown, as a continuation thereof, and outlet die 10. The soap
mixture is carried on the screw flights 11 of the screw 6. It will
be noted that toward the front end 12 of the screw 6 the pitch
distance of screw flights 11 is progressively reduced so that soap
mixture between the flights and the closely enclosing interior wall
13 of the barrel 7 is progressively compacted into a dense soap
mass which is continually urged forward toward the discharge end of
the barrel 7. Final compression occurs in the compression cone 8
and outlet die 10 through which the soap mixture is forcibly urged
by the screw 6. The highly compacted soap mass from outlet die 10
is taken for final forming as above described.
Thusfar described, the final plodder 5 is generally conventional.
The present method involves additional apparatus to the plodder in
the form of a pressure plate 14 which is known in previous plodders
to maintain adequate back pressures in the plodder barrel 7, but
which has a special purpose and configuration for use in the
invention method, and means schematically depicted in FIG. 2 for
the introduction of color contrasting colorant fluid into the
plodder 5.
With reference to FIG. 2 the saponaceous dye solution or other
colorant fluid feed apparatus is shown generally at 15 and includes
a supply tank 16, line 17, with valve 18 which is normally open
during operations, a metering pump 19 comprising a valve chamber 20
and a piston 21 mounted for reciprocal metering movement by means
not shown in cylinder 22, line 23 having ball check valve 24
against reverse dye solution flow, a pressure gage 25 and a swivel
coupling 26, connecting to a feed pipe 27 threaded axially into
rear end 28 of screw 6 for rotation therewith, for communicating
the supply tank 16 with bore 29 formed along the longitudinal axis
30 of the screw 6.
As best shown in FIG. 3 the feed pipe 27 enters the rear end 28 of
the screw 6 concentrically with counterbore 31 and drive shaft 32
which is connected to a motor (not shown) and keyed at 33 to the
screw to rotatively drive the screw 6. Bore 29 extending axially
through the screw 6 is blocked at screw front end 12 with plug 34.
A port 35 is provided forwardly and radially outward from the bore
29 terminating in an injection opening 36 on the front fact 37 of
the screw 6.
The radial offset of the opening 36 from the axis 30 of the screw 6
is to be noted to be substantially equal to that of certain of the
apertures 38 in the pressure plate 14. With this arrangement
reduced pressure zones are provided opposite the entry locus of
colorant whereby the solution may pass rapidly from opening 36
toward the apertures 38 across the space at 39 which is relatively
small, e.g. from 0.125 inches to 1 inch in a 4 inch final plodder
and generally less than 0.75 inch. The feed inlet locus is
concentric with the screw axis 30 and typically will have a radius
equal to between 35 and 65 percent of the screw radius.
It has been found providing mainly translational or axial flow from
the point of introduction of colorant fluid at opening 36 to the
pressure plate apertures 38 restricts intermixing of the dye
solution with the soap mass to a degree precluding overall tinting
of the soap mass rather than distinct color streaks, but permits a
confluence of dye solution and soap mass along the edges of the
color injection permitting achieving the desired marbled
distribution and lack of edge definition in the compression cone 8.
Accordingly the colorant fluid is desirably displaced from its
injection locus in the soap mass i.e. where it was injected into
the moving soap mass, without intimate dispersal or mixing, that
is, the injected colorant fluid moves as a coherent stream carried
by the soap mass moving between the injection opening and the
pressure plate.
Initial distribution of the dye solution or other colorant fluid
into the soap mass is realized by moving the opening 36 about a
circular locus 40 uniformly spaced i.e., equidistantly spaced from
the pressure plate (see FIG. 4) coincidentally with the screw 6
rotation. In this manner, the opening 36 and thus the point of
introduction of the colorant fluid varies through the soap mass
regularly in time. The colorant fluid may be considered to be
helically distributed through the soap mass which has passed the
opening 36 and to be substantially maintained in the helical locus
in the soap mass moving toward the pressure plate 14.
The marble effect may be increased or varied in pattern or
intensity by pulsed or constant rates of introduction of
saponaceous dye solution or other colorant fluid. Thus metering
pump 19 (FIG. 2) may be a single or multi-cylinder reciprocating
pump or constant rate of discharge gear pump operated to
correspondingly introduce intermittent or continuous quantities of
color contrasting solution into the soap mass.
The saponaceous dye solution or other colorant fluid put into the
soap mass is carried forward substantially in its injected location
subject to intermixing movement of the soap matrix to the pressure
plate 14, as described. The pressure plate apertures define zones
of lower pressure toward which the soap mass moves. By various
arrangements of these apertures in size and placement the flow rate
and direction of the soap mass may be varied and specifically the
quantity and location of the injected colorant fluid may be
controlled relative to the soap mass. In FIG. 5, pressure plate 14
is shown to have three sets of different size holes. FIrst there
are five large holes 38a at the center and at 2, 5, 8 and 11
0'clock Then there are four medium size holes 38b at approximately
12 3, 6 and 9 0'clock. In addition, there are small holes 38c
radially inward from the medium size holes 38b. In FIG. 4, the
relation of these holes 381- c to the locus 40 of injection opening
36 may be seen. As shown, injection opening 36 is directly opposite
each of holes 38c in its rotation and also is successively opposite
portions of each of holes 38a. With the spacing 39 as described and
the relative location of the apertures 38a and c successively
opposite the inlet 36 the marble pattern defining may be discerned
to be the result of helical introduction of saponaceous dye
solution or other colorant fluid into a continually advancing soap
mass with translational axial movement substantially directly
through an opposite or angularly spaced aperture which disrupts
both the solidity and the rotation of the soap mass and forces soap
mixture through the very apertures through which the saponaceous
dye solution passes. Passage into apertures 38 of the pressure
plate 14 divides the mixture momentarily into multiple strands.
After passage through the apertures, the mixture spreads
momentarily and then unites under the restrictive force of the
compression cone 8. The colorant fluid having passed through the
apertures is longitudinally distributed as the soap mass is
elongated for passage though the compression cone outlet. The
soap-colorant mixture then compresses into an integral bar as it
emerges from the forming die with the pattern creating contrasting
color saponaceous dye solution well distributed through the mass,
but without being excessively mixed therewith.
FIG. 6 shows an alternate arrangement of apertures 381 in pressure
plate 141 in which the small holes 38c have been omitted to produce
a variant marble effect which is particularly pronounced at the
soap bar surface and less persistent through the bar in use.
* * * * *